Padlocks are well known in the marketplace and are widely used to lock doors, gates and the like. Padlocks can be seen as are portable locks which can be removed from the door/gate or the like or other application when the lock is not required. This distinguishes padlocks from other forms of locks such as those that are retained in doors, windows, gates etc., including deadbolts.
Typical padlocks are formed with a strong padlock body (typically generally of brass or steel), and the padlock body usually contains a main passageway opening. A key barrel cylinder (usually in the form of a key barrel) can be fitted in the main passageway opening so that a key can be used to open the padlock (again, usually by inserting and turning a key).
Padlocks also typically have a shackle. The shackle typically generally comprises a rigid U-shaped metal member which can be formed from steel or brass. The parallel portions of the U-shaped shackle form two spaced apart parallel legs and one leg is generally longer than the other. In conventional padlocks, the longer leg passes through an opening in the top of the padlock body and is secured therein in such a manner that the leg cannot be pulled out. When the padlock is open, the secured long leg is often able to pivot about its axis so that the short leg (i.e. the other leg of the U-shaped shackle) rotates in an arc about the long leg. The longer leg of the shackle is also generally able to slide axially inwards and outwards within the opening in the body (although in conventional padlocks the shackle cannot slide all the way out of the body).
Typically, padlocks are locked by moving the shackle downwardly so that the short leg is inserted into a blind bore in the top of the padlock body. The short leg is then lockable therein to lock the padlock. The padlock can be unlocked by operating the key cylinder, and a spring is typically provided to bias the shackle to the open condition (i.e. where the short leg is retracted upwardly out of the body and can rotate about the long leg as described). Where the cylinder is a key barrel, a key can be inserted into the key cylinder barrel and turned to thereby release the shackle allowing the shackle to move upwardly into the open condition under the bias of the spring.
It will be clearly understood that, if a publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.